Timber Sash Window Maintenance Checklist

Regular inspection is the best way to reduce expensive sash window repairs.

Twice-yearly checks

Look for peeling paint, failed putty, blocked drainage, damp sills, loose fasteners and frayed cords. Open and close the window gently to check its balance.

After severe weather

Inspect exposed joints and masonry interfaces for water entry. Address persistent dampness promptly rather than painting over it.

Keep a record

Photographs and dates help identify deterioration and provide useful information when seeking professional advice.

Spring inspection

Check winter damage, loose putty, flaking paint, damp sills, opening joints and condensation patterns. Photograph any developing defects so changes can be compared later.

Summer maintenance

Clean accessible painted surfaces with a suitable mild method, clear drainage paths where present and inspect the sash’s movement. Plan paint maintenance for appropriate weather and product conditions.

Autumn checks

Check external joints and water-shedding details before persistent wet weather. Make sure fasteners engage and sashes close without being forced.

Look after the mechanism

Listen for pulley noise and check for fraying cords or uneven movement. Avoid adding oil or other products indiscriminately; use treatments compatible with the fitting and surrounding finishes.

Keep a maintenance log

Record dates, photographs, products used and any repairs. This helps future diagnosis and is especially valuable for historic properties.

When maintenance becomes repair

Soft timber, loose glazing, failing joints or a dropping sash should prompt a proper assessment rather than repeated cosmetic touch-ups.